Process for the manufacture of carbureted water gas



Nov. 3, 1931. T. w. STONE 9, 6

PROCESS FOR THE MANUFACTURE OF CARBURETED WATER GAS Filed Oct. 13. 1927 INVENTOR.

ATTO NEY.

Patented Nov. 3, 1931 UNITED'STATES PATENT OFFICE THOMAS w. salon, or roar WAYNE, INDIANA, ASSIGNOR are THE wnsrnmr eAs oousrrnuc'rronicomrm, A CORPORATION or INDI NA PROCESS FOR THE MANUFACTURE OF CABZBUBETED WATER GAS Application filed bctober 18, 1927. Serial No. 225,881.

This invention relates to the manufacture of gas, and more particularly to the manufacture of carbureted water gas inv accordance with modern improvements with respect to apparatus and process. v Among such recent improvements are the so-called back-run process of Young, U. S. Patent No. 1,468,190, and the self-clinkering generator grate. These are highly advantageous inventions, and may both be considered in attempt to build a modern and substantially ideal water-gas plant.

- I have found that the combination of these or similar improvements, while highly desirable, is not readily accomplished without a loss of efiiciency in process or apparatus, or

in both.

An object of my invention is to provide a process for the manufacture of carbureted water gas, embodying these modern improvements, but obviating certain disadvantages .in the combination thereof.

A further object of my invention is to provide a process whereby certain heat transfer relations inherent in the simple grate types of water-gas generator may be retained, even when such grates are replaced b self-cllnkering grates that have heretofore en found to destroy such relations.

My invention has for further ob]ects such other operative advantages and results may hereinafter be found to obtain.

Prior to the introduction of the back-run process, the usual construction of carbureted water-gas machines or sets provided a connection between the top of the generator and the top of the carbureter, known as the uprun connection and a further connection between the bottom of the generator and the'top of the carburetor, known as the down-run connection. A hot'valve or a lurality of coacting valves, was provided, intersecting these pi s and providing for alternately c osing tie one while'opening the other, and

vice versa.

In this type of set, which ma be designated as a hot-valve set, both up-runs and down-runs are possible, with proper manipulations of the hot valve and the steam connections to the top and bottom'of the generator. In practice, a cycle is used, roughly as follows:

(1) With the hot-valve in the normal position (up-run connection open, down-run connection closed), the generator is blasted with air, raisin the temperature of the fuel bed therein. heblow gas passes through the uprun connection into the carbureter, and is burned by means of secondary air admitted near the entrance to the latter. The hot gases of combustion traverse the checker brick within the carbureter and superheater, heating the same, and pass out of the superheater into the atmosphere or waste heat boiler through a stack valve.

(2). With the hot-valve still in the normal position, the generator blast valve, the sec ondary air blast valve and the stack valve are closed and'steam is admitted to the bottom of the generator, passing-u ward through the incandescent fuel bed an reacting therewith to form blue water gas. The blue gas passes through the up-run connection into the carbureter where oil is introduced. The oil is cracked into gaseous roducts in the carbureter and these pro ucts are permanently fixed in the gas in the superheater, thus producing carbureted water gas which passes from the superheater through the watersealed' tar batter and into the mains.

For the purpose of maintaining proper conditions within the fuel bed, it is also desirable to pass steam downward through the same during a part of the cycle, as follows:

(3') The hot-valve is reversed and steam is admitted to the top of the generator, pass-' 1 ing down through the fuel bed. The resultant blue water gas passes throu h the downrun connections into the car ureter and superheater and through the tar batter, as was true of the up-run ases. Carburetion is continued during this d own-run period.

In order to prevent an explosion, it is necessary to remove blue gas from the down-run from the lower part of the generator and from the up-run connection prior to admission of air thereto during the subsequent blow period. This isdone as follows: 5

(4) The hot valve-is again reversed into the normal position and'the flow of steam is generator, sweepmg ing loss of this valuable gas when t e stack valve is subsequently opened for the blow period.

'The reactions incident to the production of blue water gas and the subsequent carburetion thereof are endothermic and consequently the temperatures within the generator carbureter and superheater fall during the runs until it is again necessary to blast the fuel bed and burn the resultant gas to heat up the carbureter and superheater, as in (1). Thus a new cycle is commenced, consisting of periods (1), (2),'(3) and (4), as above.

During the normal operation of a simple hot-valve machine with standard grates, the

latter are protected from the incandescent zone of the fuel bed by a layer of ashes or clinkers, generally from eight to twelve inches deep, and at a relatively low temperature.

It has been found that a considerable regenerative action is exerted by this layer of ashes, which may be called the clinker zone, and the grate bars and other parts of construction at the base of the generator.. The blue water gas leaves the top of the generator during the up-run at a temperature approximately equal to that of the carbureter, but the down-run gas is cooled by the clinker zone and adjacent parts of construction, and leaves the bottom of the generator at approximately 400 to 600 F.

In a hot-valve machine, the down-run water gas leaving the generator at this low temperature traverses the carbureter and superheater for carburetion. The gas is heated therein to from about 1300 to 1400' F., and isthereafter immediately cooled in the tar batter. This means that a large amount of heat is abstracted from the carcent parts by the outgoing down-run gas is subsequently picked up by the incoming upsteam and air-blast and is moved back into .the fuel bed. That is, the steam and air en tering the fuel bed from below is preheated by just the amount of heat that has been left in this zone by the down-run gas.

The usefulness of this inherent regenerative action is not fully realized in the hotvalve machines, but produces one of the importantadvantages of the back-run process 5 and similar processes.

I In the'back-run rocess cycle, the downrun steam is introdhced beyond the superheater, passing back through the superheater and carbureter (in reverse direction to the flow of the air blast and up-run gas), and downward through the generator. The down-run gas or back-run gasthen by-passes the carbureter and .superheater, passing from the bottom of the generator through the so-called back-run pipe or by-pass pipe into the tar batter. There is ractically no loss of heat extracted from t e carbureter and superheater, as the back-run gases are cooled in the clinker zone to a relatively low temperature. Sets equipped with this process have demonstrated improved heat efficiencies in this respect.

However, it will be noted that in the backrun process, blue water gas passes through the carbureter and superheateronly during the up-run, as the back-run gas by-passes these units. Consequently, all of the oil required for proper enrichment of the total gas make must be introduced during the up-run. Even when the proportion of up-run steam to down-run steam is high, it is diflicult to properly carburet' the gas.

Now when the water-gas generator is improved by substituting a self-clinkerin'g grate for the simple type of grates used heretofore, it is found that an entirely different condition exists.

For example, in one type of self-clinkering grate that is being used in actual practice with great promise of success, a water-cooled beam or plow is slowly rotated over a stationary grate. The -fire is continuously stirred in an upward and outward direction, and the ashes are removed continuously. In order to effect satisfactory operation of this advantageous device, the fire is kept down very close to the grate, and the entire grate region is at a very much-higher temperature than is true of the clinker zone of the old type of generator. Consequently, the down-run gas leaving the bottom of the generator is not cooled as in prior practice, and in fact leaves the generator at a temperature of about 800 to 1000 The full economy. of such a process is therefore not fully realized when it is performed in a water-gas set equipped with a self-clinkering grate.

Moreover, the up-steam and the air blast are not preheated before they reach the high temperature reactive zone of the fuel bed, as is true in the ordinary water-gas set. For this reason, it is necessary to increase the proportion of down-steam (or back-run steam) to offset the considerable cooling effect of the unpreheated up-steam and upair. This means that the-length of time of the up-run will necessarily be decreased, thus exaggerating the unfavorable condition inherent in the back-run process, namely that Z tar batter. ln this manner, it is possible to all the oil must 'crowded' into the carbureter during the all too brief up-run.

It will thus be seen that some of the advantages of the back-run process disappear th when practiced in a water-gas set equipped with a self-clinkering generator grate, and that the full development of the water-gas machine and process is hindered by these facts.

According to my invention, I provide means whereby the back-run or a similar process may be adapted to performance in a water-gas set equipped with a self-'clinkering generator grate, without loss of efiiciency, and without losing certain advantages of each which have heretofore been lost in the combination of the two.

I accomplish this object by" providin a regenerator inserted in the'back-run pipe between the bottom of the generator and the v and performed.

In this drawing, 7

The single figure is a view, partially in elevation and partially in section, of a carburetor water-gas set constructed in accordance with'thepre'sent invention.

There is provided as usual a water-gas generalor 1, a carbureter 2, a superheater 3, and

a tar batter, wash box or gas ofi'take seal 4.

The generator is provided with a fuel-charging door 5, which is shown as of the manual type, but which may be provided with an automatic charging device such as the How ard and Stone automatic charger that is the subject of U. S. Patent No. 1,597,314.

The generator 1 is further provided with a self-clinkering grate device 6, the details of the specific device shown being the invention of another. In this grate device, a sub stantially horizontal water-cooled beam- 7 and integrally attached ash-pan 8 are slowly fuel bed, the beam 7 being of substantially triangular cross-section, and passing over the surface of a fixed grate 9, imparting a slowly undulating movement to the fuel-bed, the bulk of the ash being slowly and continually removed from the fuel-bed as it is formed. and discharged at 11. Some fine ash passes through the grate 9, falling ino the hopper 12, and is removed as desired through the trap door 1?.

The tops of the generator 1 and the carbureter 2 communicate through an up-run connection 14, having a dust pocket 15 therein. Communicating with the up-run connection 14 there is provided a secondary air supply pipe 16, having a valve 17 situatedv erein.

or up-run connection 14 already referred to, an oil spray 18, and a base outlet pipe 19 communicating with the base of the superheater 3.

v The superheater 3 is provided, in addition 75.

to the base inlet pipe 19, with a stack valve 21, and an outlet 22 leading to the tar batter 4. The carbureter 2 and superheater 3 are of the usual type, being filled with checkerbrick disposed in the usual manner.

Inserted in the pipe 22 is a back-run steam supply line 23, that is provided with a valve 24. The pipe 22'enters the tar batter 4 and is sealed with liquid therein. The tar batter 4 may be of any of the double inlet types, but

the preferred construction is that shown and described in the copending patent application of Thomas W. Stone and Fred B. Hayes, Serial No. 232,515, filed November 11, 1927,

the details of. which need not be described here.

Communicating between the bottom of the generator 1 and the tar batter 4 is a so-called by-pass or back-run pipe 25, wherein is situated a regenerator 26. This regenerator 26 is in its preferred form constituted of a suitable refractory-lined shell 27 of substantially cylindrical configuration. The-interior of the regenerator is filled with checkerbrick 28, mo

dis osed in the usual manner. (lbmmunicating with the back-run pipe 25 at points between the regenerator 26 and the tar batter 4 are provided a generator air-blast supply pipe 31 having a valve 32 therein, and

an up-run steam supply line 33, having a valve 34 therein.

The tar batter 4 is provided with a valve member (not shown) adapted to alternately positively prevent flow of gas from the pipe 25 while permitting flow of gas from pipe 22 no and vice versa, while flow of gas from either the pipe 22 or the pipe 25 is possible only through a water seal that serves to prevent reversal of flow through either of these pipes.

The gas after traversing this seal passes out 15 .of the tar batter4throu h a i e35 t h and continuously rotated at the base of the g p p m 0t 8 1) The valve 32 is opened, and primary 125 air enters the back-run pipe 25, and passes through the generator 26 that has been heated by a previous cycle, as will be shown in cohnection with this cycle. The air is here preheated to about 800 to 900 The carburetor 2 is provided with the inlet 70 F. and then no enters the bottom of the generator 1, passing:

upward through the fuel bed therein, raising its temperature and. enerating producer or blow gas. The hot b ow gas passes through the up-run connection '14 into the carbureter 2, and is burned by means of secondary air admitted from pipe 16, valve 17 being opened. The hot and burning gases traverse the carbureter 2, the pipe 19 and the superheater 3, heating the checkerbrick within the carbureter and superheater -to from about 1000 to 1500 F., and the products of combustion pass out of the superheate'r 3 into the atmosphere through the now open stack valve 21. During this blow period, no gaspasses through the tar batter 4.

When'the temperatures of the fuel bed within the generator 1 and the checkerbrick within the carbureter 2 and superheater 3 are sufiiciently high, valves 32, 17 and 21 areclosed.

(2) Steam is now admitted to the back-run pipe 25 through the line 33 by opening the valve 34, and it passes through the regenerator 26, being preheated therein on its: way

to the generator 1. The water gas produced in the generator by this preheated steam flows upward through the up-run connection 14 into the carbureter 2. Oil is now admitted through'the'spray 18, and, falling upon the previously heated checkerbrick within the carbureter-2, is cracked thereby and enriches the blue gas, forming carbureted water gas.

Enough oil is introduced during this up-run g period to provide for. the required thermal value of the final mixture of .carbureted and uncarbureted gas.

(-3) Steam is now admitted through the line 23. valve 24 being open, and passes through pipe 22, the'superheater 3, pipe 19, the carbureter 2 and pipe 14, into thegenerator 1.

- .The back-run steam passes downwardly through the fuel bed within the generator 1,. and theresultant blue water gas, at a temperature of about 8'00-'-1000 F., passes through the back-run pipe 25 into the regenerator 26. Here the" blue gas is cooled by contact with the checkerbrick 28 to approximately 400 F. or lessand then it passes to the tar batter 4, traversing the seal therein and passing thence through pipe. 35 to a gas holder, not shown.

During this back-run period, the heat that i is being carried out of the fuel bed by the back-run gas is accumulated in the regenerator 26, particularly in thelower portion thereof.

(-5) In order to prepare for the next blow, the back-run is followed by a short steam up-run, the tar batter valve being reversed, valve 24 closed and valve 34 open. Steam now traverses the regenerator 26, being preheated therein, and sweeps the blue water gas from the preceding back-run ahead of it into the generator 1. The cycle is now self-clinkering grate is employed.

Moreover, since the airand steam entering the generator from below are preheated, undesirable cooling eflects upon the fuel bed and grate device are avoided. For this reason, theproportion of up-run steam to backrun steam maybe considerably greater than would otherwise be possible, andconsequently the length of the un-run period. during which all the carburetion necessary to provide enrichment for the total gas make must be accomplished, is correspondingly increased. This makes it easier to accomplish this carburetion, which is of necessity performed at a high rate of oil injection, even under less crowded conditions.

To further illustrate the utility of my invention, the following typical results obtained in practice are presented.

In the ordinary hot-valvecarbureted wateras set, the amount of down-steam is about half of the total steam, ranging from about 45 to 55 percent of the total steam input. Garburetion takes place during both the uprun and the down-run.

When a hot-valve set is'equipped with a self-clinkering generator, the proper use of the latter requires that the down-steam be about 70% of the total. So long as carburetion occurs durin both the up-run and the down-run, no di culty in attaining the desired enrichment is encountered.

However, in the use of the back-run process, it is usually diflicult to increase the amount of back-run steam (down-steam) to more than about 40 to 50% of the total steam input, as carburetion is possible only during the up-run. With high requirements, it becomes even more difiicult to use this much back-run steam.

It will thus clearly be seen that it is difficult to practice the back-run process, which requires a high percentage of -up-run steam, in conjunction with a self-clinkering grate device, the proper use of which requires a .high percentage of down-run steam, unless the grate device is avoided, and consequently a higher percentage of up-run steam may be employed than would otherwise be true, thus permitting longer carburetion periods, and the use of the back-run process, as well as conserving one of the main advantages inherent in the latter.

While I have hereinabove described my 1nvention with relation to a certain process or cycle known as the back-run process, it is not limited to this specific process or cycle, but may be applied with beneficial results to any process similar to this process 1n that the down-run gas by-passes the carbureter and superheater, passing directly (or, as 1n the present invention, via a regenerator) from the bottom of the generator to the tar batter. The so-called dowrr-run' process and the by-pass process are examples of processes of this type, wherein the down-run steam is introduced at the top of the generator, and flows from the base of the generator to the tar batter.

I designate any such process, thereln the down-run or back-run'gas by-passes the carbureter and superheater on its way from the bottom of the generator to the tar batter, as a by-pass process, including such processes as the back-runp'rocess, the down-run process, and the like, thereunder.

While I have hereinabove described and set forth my invention with respect to a specific. example and embodiment, I do not limit myself to suchillustrative instances, except as I may do so in the following claims.

I claim as my-invention:

1. The process of manufacturing carburetedwater gas which, when carried out in an apparatus comprising a single generator having a bed of solid fuel, a single carbureter, -a single superheater, a regenerator containing a body of refractory and heat-accumulative material contiguous to and connected with the base of the generator, and a gasoiftake seal connected to said superheater and said regenerator, comprises: first air blasting the generator fuel bed to heat the same, conducting the resultant gas through said carbureter and superheater and burning it therein to heat the same; subsequently passing steam back through said superheater and carbureter and then downward through said generator fuel bed, conducting the hot backrun water gas thereby produced through said regenerator to heat the same and cool said gas, and withdrawing said backrun gas through said gas offtake seal; at intervals subsequent to said air blasting period and said back steaming periodpasslng steam through said thereby heated regenerator, conducting the thereby preheated steam upward through said generator fuel bed, conducting resultant uprun water gas through the heated carbureter and superheater andcarbureting it during its passage through sald carbureterand suand withdrawing said backrun water perheater by'introducing oil thereto in said carbureter and withdrawing the thereby carbureted uprun water gw through said gas offtake seal; and substantially continuously removing ash from said fuel bed at a rate corresponding to the rate at which ash is formed by the action of said air and steam upon said fuel bed; whereby heat carried out of the generator fuel bed by said air and said uprun water gas is recovered and returned to said fuel bed by said backrun steam, and sensible heat carried out ofthe generator fuel-bed by said hot backrun water gas is recovered and returned to said generator fuel bed by said uprun steam, and the bottom of said fuel bed is maintained in a highly heated condition facilitating the substantially continuous removal of ash therefrom, without sacrifice of thermal economy.

2. The process of manufacturing carbureted water gas which, when carried out in an apparatus comprising a single generator having a bed of solid fuel, a single carbureter, a single superheater, a regenerator containing a body of refractory and heat-accumulative material contiguous to and connected with the base of the generator, and a gas offtake seal connected to said superheater and said regenerator, comprises: first blastmg air through said regenerator-and upward through said generator fuel bed to heat the latter, conducting the resultant gas through said carbureter and superheater and burning it therein to heat the same; then passin steam upward throu h said generator fue bed, conducting resu tant uprun water gas through the heated carbureter and superheater and carbureting it during its passage therethrough by introducing oil to said carbureter, and withdrawing the therebycar bureted uprun water gas through sa1d gas offtake seal; and then passing steam back through said heated superheater and carbureter and downward through said generator fuel bed, conducting the resultant backrun water gas through said regenerator to heat the latter and cool said backrun water gas as through said gas oiftake seal; and subst ntially continuously removing ash from said generator fuel bed at a rate corresponding to the rate at which ash is formed by the action of said air and steam upon said fuel bed; whereby heat carried out of said generator .fuel bed by said air and said u run steam is recovered and returned to said 2161 bed by said backrun steam, and sensible heat carried out of said generator fuel bed by said hot backrun water gas is recovered and returned to said generator fuel bed by said air blast, and the bottom of said fuel bed-is maintained in'a highly heated condition facilitating the substantially continuous removal of ash therefrom, without sacrifice of thermal economy.

3. The process of manufacturin carbureted water gas which, when carrie out in an apparatus comprising a single generator havinga bed of solid fuel, a single carbureter, a single superheater, a regenerator containing a body of refractory and heat-accumulative material contiguous to and connected with the base of the generator, and a. gas ofitake seal connected to said superheater and said regenerator, comprises: first blasting air through said regenerator and upward through said generator fuel bed, conducting the resultant gas through said carbureter and superheater and burning it therein to heat the same; then passing steam through said regenerator and upward through said fuel bed, conducting resultant uprun water gas through the heated carbureter and superheater and carbureting it during its passage therethrough by introducing oil to said carbureter, and withdrawing the resultant carbureted water gas through said gas ofl',- take seal; and then passing steam downward through said. generator fuel bed, conducting the resultant hot downrun water gas through said regenerator toheat the latter and cool said downrun watergas and withdrawing saiddownrun water as through said gas off take seal; and substantially continuousl removing ash from said generator fuel be at a rate corresponding to the rate at which ash is formed by the action of said air and steam upon said fuel bed; whereby sensible heat carried out of said generator fuel bed by said hot downrun water gas is recovered and returned to said generator fuel bed by said air blast and said. uprun steam, and the bottom of said generator fu'el bed is maintained in a highly heated condition facilitating the substantiall continuous removal of ash therefrom, without sacrifice of thermal economy.

4. The process of manufacturing carbureted water gas which, when carried out in an apparatus comprising an-single generator having a bed of solid fuel, a-single carbureter, a singlesuperheater, a regenerator containing a body of refractory andheat-accumulative material contiguous to and connected with the base of the generator, and a gas ofi"- take seal connected to said superheater and said regenerator, comprises: first blasting air through said regenerator and upward through generator fuel bed, conducting ,the

' resultant gas through said carbureter and superheater and burning it therein to heat the same; then passing steam through said regenerator and upward through said fuel bed, conducting resultant uprun Water gas through the heated carbureter and superheater and carbureting it during its passage therethrough by introducing oil to said carbureter, and withdrawing the resultant car bureted water gas through said gas ofl'take seal; and then passing steam back through said heated superheater and carbureter and downward through said generator fuel bed, conducting the resultant hot backrun water gas through said regenerator to heat the latter and cool said backrun water gas, and withdrawing said backrun water gas through said gas ofl'take seal; and substantially continuously removing ash'from said generator fuel bed at a rate corresponding to the rate at which ash is formed by the action of said air and steam upon said fuel bed; whereby heat carried out of said generator fuel bed by said air blast and said uprun steam is recovered and returned to' said fuel bedby said backrun steam, and sensible heat carried out of said generator fuel bed by said hot backrun water gas is recovered and returned to said fuel bed by said air and said uprun steam, and the bottom of said fuel bed is maintained in a highly heated condition facilitating the substantially continuous removal of ash, therefrom, without sacrifice of thermal economy.

In testimony whereof, I have hereunto sub scribed my name this 8th day of October,

THOMAS W. STONE.

CERTIFICATE or CORRECTION.

Patent No. 1,829,767. Granted November 3, 1931, to

THOMAS w. STONE.

It is hereby certifiedthat error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 11, after the word "in" insert the word an; page 4, line 116, after "high" insert B. t.u.; and' that the said Letters Patent should he read with these corrections therein that the same may conform to therecord of the case in the Patent Office.

Signed and sealed this lSth day of December, A. 1). I931.

M. J. Moore,

(Seal) Acting Commissioner of Patents. 

